1. Field of the Invention (Technical Field)
The present invention relates to an oil drilling tool assembly comprising a bit release subassembly, a test sleeve that is removable to open and close flow ports, and a profile nipple.
2. Description of Related Art
Note that the following discussion refers to a number of publications by author(s) and year of publication, and that due to recent publication dates certain publications are not to be considered as prior art vis-a-vis the present invention. Discussion of such publications herein is given for more complete background and is not to be construed as an admission that such publications are prior art for patentability determination purposes.
Well bore tool assemblies used in the oil drilling industry may include a sliding sleeve that opens flow ports. However, when utilizing a bit release subassembly, no sliding sleeve and/or profile nipple are typically included in the tool assembly. A bit release subassembly is a component of a drilling tool assembly that is designed to detach from the overall assembly when the assembly is ready to be placed in production mode. When the bit release subassembly is released, the drill bit is also released to fall to the bottom of a well. Sliding sleeves are incorporated into a tool assembly so that when activated, flow ports are opened. If a sliding sleeve is combined with a bit release subassembly, it is activated to open the flow ports in conjunction with other events, such as pumping off (i.e., releasing) the bit release subassembly, that prevent further testing. Therefore, multiple zones cannot be tested individually when testing a well. Also, combining a sliding sleeve and a bit release subassembly would result in an assembly of excessive length because, for example, the tools would have to be spaced apart at a pup joint to function properly.
An apparatus or method is needed that provides the ability to put the drilling apparatus in a test-flow position by opening the flow ports, then return the apparatus to a drill-out position to continue testing multiple zones down into the well that is being tested.